Type of Carbs Eaten Affects Gas Production and Symptoms in IBS

It is not uncommon for patients with IBS to complain of symptoms worsening when eating foods rich in carbohydrate such as bread, pasta, rice, cereals or potatoes. However a recent study suggests that rather than avoiding this whole food group (which can be difficult for many patients to comply with), relief may be obtained by altering the ‘types’ of carbohydrate foods eaten. Some carbohydrate foods contain sugars and sugar alcohols that are difficult to absorb and these are collectively called FODMAPS (fermentable oligo-di and mono sacharides and polyols) Foods high in FODMAPS include wheat, apples, pears, prunes, milk, beans and lentils, while foods containing low levels include bananas, blueberries, raspberries, hard cheese, carrots and rice.

In the study, 15 healthy subjects and 15 with IBS (Rome 111 criteria), undertook a single – blind, crossover intervention trial in which foods containing FODMAPS were either low (9g per day) or high (50g per day). Diaries were kept in which participants recorded diet intake and gastrointestinal symptoms and breath samples were collected hourly over 14 h on day 2 of each diet. When the breath samples were analysed higher levels of breath hydrogen were produced over the entire day with the high FODMAPS diet for health volunteers and patients with IBS Gastronintestinal symptoms and lethargy were significantly worse with the high FODMAPS diet in patients with IBS. The authors concluded that ‘Dietary FODMAPS induce prolonged hydrogen production in the intestines that is greater in IBS, influence the amount of methane produced and induce gastrointestinal and systemic symptoms experienced by patients with IBS’

Source: Manipulation of dietary short chain carbohydrates alters the pattern of gas production and genesis of symptoms in Irritable Bowel Syndrome’ Journal of Gastroenterol Hepatol 2010 Aug 25 (8): 1335-6